Morton County Sheriff Kyle Kirchmeier, front, listens to Brian Wesley Horinek of Oklahoma outside the New Camp on Pipeline Easement in North Dakota, Oct. 26, 2016. Kirchmeier, who has led the police response to the Dakota Access oil pipeline, is a law enforcement lifer, a veteran of the North Dakota State Patrol and National Guard before being elected to his first term as Morton County sheriff. Tom Stromme The Bismarck(N.D.) Tribune/AP

Morton County Sheriff Kyle Kirchmeier, front, listens to Brian Wesley Horinek of Oklahoma outside the New Camp on Pipeline Easement in North Dakota, Oct. 26, 2016. Kirchmeier, who has led the police response to the Dakota Access oil pipeline, is a law enforcement lifer, a veteran of the North Dakota State Patrol and National Guard before being elected to his first term as Morton County sheriff. Tom Stromme The Bismarck(N.D.) Tribune/AP